devmar07

Yesterday I was breaking in my new sbc and it started fine with quite a it of smoke which I'm told is normal at first. I put the timing light on it and noticed it was severely retarded before I could get the timing right it started get hot so I shut it down. I went to work on it today and noticed oil around and exhaust port so I pulled a plug and it have a lot of oil on it. Is it normal for a new engine to do this because the rings haven' seated or do I have a bigger problem.

devmar07

I have done a compression test and 1,3,5 and 7 were between 155 and 170 and 2,4,6 and 8 were between 145 and 125 I'm in the process of doing a leak own test and on cylinder 1 I have 50 percent leakage and it appars to be the valves. Now everything is new and both tests are being done cold other than testing the rest of the cylinders what do I do next.

oldcutlass

Set your timing quickly and finish your cam break in, let the rings seat.

cutlassefi

What rings and oil are you using?

devmar07

I just finished the leak down test and every valve is leaking a little I don' think I trust the harbor freight gauges but at least I can see and hear where the air is coming from. So I should put it back together and run this engine for awhile.

devmar07

not sure about rings but I have 5w 30 with Lucas zinc additive even though I have a hydraulic roller cam

cutlassefi

Who’s 5w-30?
Rings are best seated with a load on them. Since you have a roller cam, set the timing etc and take it for a short drive if all else is good. Then check it after that.

oldcutlass

Didn't realize you had a roller cam. Are you sure your lifter preload is set correctly?

devmar07

I took all the rocker right off then put air though the cylinder and it' blowing right past the exhaust valves

cutlassefi

I think it’s time to remove the heads.

devmar07

it's looking that way I'm going to call my local speed shop tomorrow and get a quote on repairing the heads. I still think it' it's how they all leak. Why would someone rebuild something then not check if the valve are seated

oldcutlass

Where did you get your new sbc?

devmar07

from a guy selling a project car he started. I just bought the engine and tranny.

devmar07

all the parts I can see are new and the rod numbers match the cam he said was in it.

Greg Rogers

If rockers are too tight will it hold valves open??

cutlassefi

Huh? What rod numbers? Match the cam? I’m confused.

Sugar Bear

Compression numbers are notably different from one bank to the other and that is not the oil problem but... check to see if the heads are a matched pair? Has one head been milled more than the other? Are the head gaskets the same thickness?

Good luck!

devmar07

the push rods are 7609 comp cam magnums which go will the big ***** thumper roller cam he said was in it now I haven' seen the cam shaft but the push rods confirm it.